The present invention relates generally to integrated circuit packaging and, more particularly, to a ball grid array (BGA) or lan grid array (LGA) semiconductor package including an embedded leadframe for allowing the vertical stacking of an LGA or leadframe package thereupon.
A staple component of the electronics industry is a ball grid array (BGA) semiconductor package. BGA packages typically comprise a substrate having a plurality of array-arranged solder balls on the bottom surface thereof. The solder balls act as I/O (input/output) connections for a semiconductor die which is attached to the opposite, top surface of the substrate. In this regard, the substrate is typically provided with a conductive pattern (e.g., pads, traces, vias, etc.), with the semiconductor die being electrically connected to the conductive pattern which is used to route signals from the semiconductor die to the solder balls. The semiconductor die is typically covered by a hardened encapsulant which also covers the top surface of the substrate and defines the package body of the BGA package. Thus, the solder balls deposited on the bottom surface of the substrate are used to electrically connect the semiconductor die to an external device, e.g., a printed circuit board (PCB). The conductive pattern of the substrate may be configured so as to facilitate the electrical connection of the semiconductor die to differently functioned solder balls to allow the BGA package to operate with multiple functions of grounding, powering, and signaling.
One of the notable drawbacks of currently known BGA packages is the absence therein of any elements which allow for the stacking of a second semiconductor package thereon. The increased signal processing and memory requirements of many electronic devices, coupled with the need to occupy a minimal amount of space within such devices, makes it highly desirable for BGA or LGA packages to be configured to allow for the stacking of a second semiconductor package thereupon. The present invention addresses this deficiency by providing a BGA package with an embedded leadframe which allows for the stacking of a second semiconductor package such as an LGA or leadframe package on top of the package. These, as well as other features and advantages of the present invention, will be described in more detail below.